• Development and Reproduction
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• v.16 no.2
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• pp.129-135
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• 2012

Previously, we identified that the overexpression of IEX-1 induces apoptosis in ovarian cancer cells. Herein we report a new binding partner of IEX-1, CATHEPSIN B, as a lysosomal enzyme which contributes to the various apoptotic signaling in tumor cells. To investigate how IEX-1 regulates cellular survival and death event, we performed yeast two-hybrid screening of rat ovarian cDNA library using IEX-1 as the bait and found CATHEPSIN B. In the present study, CATHEPSIN B and IEX-1 proteins were overexpressed in 293T cells and their specific association was determined by immunoprecipitation and immunoblot analysis. In addition, the endogenous interaction between CATHEPSIN B and IEX-1 was confirmed in HeLa cells. The current finding of lysosomal CATHEPSIN B as the IEX-1-binding partner implies that IEX-1 may involve in lysosome-mediated apoptotic signaling pathways.

• KDI Journal of Economic Policy
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• v.37 no.sup
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• pp.33-63
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• 2015

This paper attempts to investigate the Korean households' inflation expectations with particular attention to information rigidity. For this purpose, we derive an empirical model from a sticky information model $\acute{a}$ la Mankiw and Reis (2002) and estimate it. In addition, it is also examined whether the expectation formation is state-dependent on macroeconomic conditions. The main findings of this paper are as follows. First, it turns out that the information rigidity in Korean households' inflation expectations is very high. In a month, most of the households simply keep their inflation expectations the same as before instead of updating them based on newly arrived information. Furthermore, when updating their expectations, the households tend to rely on the backward-looking information such as actual inflation rates in the past rather than on the forward-looking forecasts by experts. Second, it is found that the expectation formation is varying as inflation rate changes. Specifically, when the inflation is high, the sensitivity of the households' inflation expectations to actual inflation increases and the gap between inflation expectations and actual inflation shrinks. It implies that Korean households update their expectations more frequently when the inflation matters than not.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.10
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• pp.1373-1380
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• 2014

The thyroid hormone responsive protein (THRSP) gene is a functional gene that can be used to indicate the fatty acid compositions. This study investigates the relationships of exonic single nucleotide polymorphisms (SNPs) in the THRSP gene and fatty acid composition of muscle fat and marbling score in the 612 Korean cattle. The relationships between fatty acid composition and eight SNPs in the THRSP gene (g.78 G>A, g.173 C>T, g.184 C>T, g.190 C>A, g.194 C>T, g.277 C>G, g.283 T>G and g.290 T>G) were investigated, and according to the results, two SNPs (g.78 G>A and g.184 C>T) in exon 1 were associated with fatty acid composition. The GG and CC genotypes of g.78 G>A and g.184 C>T had higher unsaturated fatty acid (UFA) and monounsaturated fatty acid (MUFA) content (p<0.05). In addition, the $ht1^*ht1$ group (Val/Ala haplotype) in a linkage disequilibrium increased MUFAs and marbling scores for carcass traits (p<0.05). As a result, g.78 G>A and g.184 C>T had significantly relationships with UFAs and MUFAs. Two SNPs in the THRSP gene affected fatty acid composition, suggesting that GG and CC genotypes and the $ht1^*ht1$ group (Val/Ala haplotype) can be markers to genetically improve the quality and flavor of beef.

• BMB Reports
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• v.41 no.2
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• pp.119-125
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• 2008

Our previous work confirmed that Sph2/LA1029 was a sphigomyelinase-like hemolyisn of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai. Characteristics of both hemolytic and cytotoxic activities of Sph2 were reported in this paper. Sph2 was a heat-labile neutral hemolysin and had similar hemolytic behavior as the typical sphingomyelinase C of Staphylococcus aureus upon sheep erythrocytes. The cytotoxic activity of Sph2 was shown in mammalian cells such as BALB/C mouse lymphocytes and macrophages, as well as human L-02 liver cells. Transmission electron microscopic observation showed that the Sph2 treated BALB/C mouse lymphocytes were swollen and ruptured with membrane breakage. They also demonstrated condensed chromatin as a high-density area. Cytoskeleton changes were observed via fluorescence confocal microscope in Sph2 treated BALB/C mouse lymphocytes and macrophages, where both cytokine IL-$1{\beta}$ and IL-6 were induced. In addition, typical apoptotic morphological features were observed in Sph2 treated L-02 cells via transmission electron microscope and the percentage of apoptotic cells did increase after the Sph2 treatment detected by flow cytometry. Therefore, Sph2 was likely an apoptosis-inducing factor of human L-02 liver cells.

• BMB Reports
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• v.50 no.6
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• pp.335-340
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• 2017

Although doxorubicin (Dox)-induced oxidative stress is known to be associated with cytotoxicity, the precise mechanism remains unclear. Genotoxic stress not only generates free radicals, but also affects actin cytoskeleton stability. We showed that Dox-induced RhoA signaling stimulated actin cytoskeleton alterations, resulting in central stress fiber disruption at early time points and cell periphery cortical actin formation at a later stage, in HeLa cells. Interestingly, activation of a cofilin phosphatase, chronophin (CIN), was initially evoked by Dox-induced RhoA signaling, resulting in a rapid phosphorylated cofilin turnover leading to actin cytoskeleton remodeling. In addition, a novel interaction between CIN and $14-3-3{\zeta}$ was detected in the absence of Dox treatment. We demonstrated that CIN activity is quite contrary to $14-3-3{\zeta}$ binding, and the interaction leads to enhanced phosphorylated cofilin levels. Therefore, initial CIN activation regulation could be critical in Dox-induced actin cytoskeleton remodeling through RhoA/cofilin signaling.

• Korean Journal of Logic
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• v.16 no.1
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• pp.61-85
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• 2013

The author, after introducing the concept of de re belief and discussing de re/de dicto ambiguity in belief context and modal context, concludes that modal sentences of Korean language does not show any distinctive traits against English. He, after discussing this ambiguity in negative sentence a la Russell, tries to show that Korean provides two way of negation construction, one of which corresponds to de re negation (primary occurrence in Russell's terms). De re reading makes referentially transparent context, thus permits substitutions of identicals salva veritate; De dicto reading does not. Korean ending 'rago', used with quotation verbs, speech act verbs and cognitive attitude verbs, deserves some attention in that it permits de re sentences in addition to de re/de dicto ambiguous sentences. 'Rago' also makes speaker's commitment to the content of the intensionally contained clause 'neutral', in contrast with other Korean endings such as 'um/im' and 'raneun gut' which make speaker's positive commitment. This explains why the maxim of western epistemology that knowledge presupposes truth does not hold in Korean 'rago' sentences.

• Journal of the Mineralogical Society of Korea
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• v.13 no.3
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• pp.147-163
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• 2000

The mineralogy and chemical composition of reddish to brownish yellow residual soils, so called "Hwangto" have been examined according to representative host rocks. The result of the study indicates that Hwangto consists of 40-80% clay minerals and various minerals such as quartz, feldspar, hornblende, goethite, and gibbsite. Clay minerals include kaolinite, halloysite, illite, hydroxy interlayered vermiculite (HIV), mica/vermiculite interstratifield mineral and chlorite. The mineralogical constituents and contents of Hwangto were different depending on the types of host rocks. Moreover, the Jurassic granitic rocks contain relatively more kaolin minerals, whereas the Cretaceous granitic rocks contain more HIV and illite. In addition, reddish Hwangto contains relatively more kaolinite and HIV, and yellowish Hwangto contains more illite and halloysite. It is suggested that feldspars and micas of host rocks were chemically weathered into illite, halloysite, illite/vermiculite interstratified minerals, and HIV, and finally into kaolinite. Compared with their host rocks, the major chemical compositions of Hwangto tend to contain more $Al_2O_3,\;Fe_2O_3,\;H_2O$ in amount and less Ca, Mg, and Na. Hwangto contains relatively high amount of trace elements, P, S, Zr, Sr, Ba, Rb, and Ce including considerable amount of Li, V, Cr, Zn, Co, Ni, Cu, Y, Nb, La, Nd, Pb, Th in excess of 10 ppm. Relatively high amount of most trace elements were detected in the Hwangto. The major and minor chemical compositions of the Hwangto were different depending on the types of host rocks. However, their difference was in the similar range compared with the compositions of host rocks.

• Reproductive and Developmental Biology
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• v.40 no.2
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• pp.15-22
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• 2016

As a one of unsaturated fatty acid, polyunsaturated fatty acids (PUFAs) have multiple actions: as precursor of prostaglandins (PGs), steroid hormone synthesis and energy production in animal reproduction. PUFAs, which include omega-3 (n-3) and omega-6 (n-6), are derived from the diet and changed by diet, species, breed and season. The plasma membrane of spermatozoa in mammals contain various PUFAs. These composition of PUFAs regulate the membrane fluidity and cause lipid peroxidation via generation of reactive oxygen species (ROS). Induced lipid peroxidation by ROS decreased viability and motility of spermatozoa, and it is reduced by addition of antioxidant and low concentration of PUFAs. Because oocytes of animal have a high lipid components, process of oocyte maturation and embryo development are influenced by PUFAs. In in vitro study, oocyte maturation, embryo development, intracellular cAMP and MAPK activity were increased by treatment of n-3 ${\alpha}$-linolenic acid (ALA) during maturation, whereas n-6 linoleic acid (LA) negatively influenced. Also, inhibition of fatty acid metabolism in oocyte influenced blastocyst formation of cattle. PGs are synthesized from PUFAs and various PUFAs influence PGs via regulation of PG-endoperoxide synthase (PTGS). Steroid hormone synthesis from cholesterol is regulated by expression of steroid acute regulator (StAR) protein and mRNA. Exogenous n-3 and n-6 PUFAs altered sex hormone in animal through stimulate or inhibit StAR activity. Because PUFAs altered PG and steroid hormone synthesis, follicular development was influenced by PUFAs. This effect of unsaturated fatty acid could provide information for improvement of reproductive ability in animals.

• Korean Journal of Ecology and Environment
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• v.48 no.4
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• pp.272-279
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• 2015

The aim of this study was to assess the interaction between Daphnia similis and various organisms related to the rice paddy ecosystem. We selected several organisms that are likely to prey on D. similis and evaluate predation rate as well as responses of D. similis to the chemical compounds exuded by these organisms. As a result of predation experiment, larval dragonfly (Anax parthenope) and Triops longicaudatus were clearly shown decreasing abundances of D. similis. Especially, Triops longicaudatus was observed higher feeding rates on D. similis than larval dragonfly. Chemical compounds from the vertebrates such as fish (Misgurnus anguillicaudatus, Pseudorasbora parva, Micropterus salmoides) and tadpole of frog (Rana nigromaculata) did not affect the life history of Daphnia. However, a potential predatory fish P. parva induced significantly longer tail spine in Daphnia. In addition, among the invertebrates (T. longicaudatus, A. Parthenope, Micronecta spp., Palaemon paucidens), chemical compounds exuded by T. longicaudatus induced shorter body and significantly longer tail spine in D. similis.

• Korean journal of food and cookery science
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• v.26 no.2
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• pp.155-164
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• 2010

The present study attempted to conceptualize Korean typical tastes, flavors and foods and to gather professionals' opinions about the globalization of Korean foods. A total of 23 experts participated in a three round survey using the Delphi technique, which was used to integrate and share the professional ideas of each expert. The survey was categorized into two parts: 1. Korean typical tastes and flavors, 2. Korean typical foods. According to the results, 'hot chili pepper', 'Kimchi', 'soy sauce', and 'garlic' were represented as Korean typical tastes and flavors. Also 'harmonized' was determined to be a type of food that should be introduced to foreigners and, 'sweet' and 'tart' were shown to also be liked by foreigners. In addition, 'neobiani', 'kalbi', 'bibimbap', 'kimchi', 'japchae', and 'neobiani' were categorized as typical Korean foods, foods that should be introduced to foreigners, and foods that would be liked by foreigners. These results showed that appropriate foods should be globalized and R&D should be expanded to determine the preferences of foreigners in terms of tastes and flavors.